In this paper, a new method for preparing ultrafine tungsten-molybdenum composite powders has been proposed. The carbothermic pre-reduction of the mixture of molybdenum trioxide and tungsten trioxide with insufficient carbon black under argon atmosphere was carried out, to generate the pre-reduced tungsten-molybdenum composite powder containing a small amount of residual dioxide. Thereafter, the obtained reaction product was subjected to hydrogen reduction to remove the residual dioxide and generate pure tungsten-molybdenum composite powder with the particle size of 100–200 nm. Two kinds of ultrafine tungsten-molybdenum alloy powders (Mo-30 wt% W, Mo-70 wt% W) were prepared. The residual carbon of the finally obtained product was about 0.01–0.02 wt% after the hydrogen reduction. The sintering behavior of ultrafine W–Mo powders and the properties of sintered samples are investigated. After sintering ultrafine Mo-30 wt% W and Mo-70 wt% W powders at 1600 °C, the relative density of the sintered compacts was about 99%, 97%, and the microhardness were 287 HV and 350 HV, respectively. Meanwhile, as increasing the sintering temperature from 1200 to 1600 °C, the relative density and microhardness of the compacts gradually increased.

中文翻译：

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钨钼超细粉的制备及其烧结行为

本文提出了一种制备超细钨钼复合粉的新方法。在氩气气氛下对碳黑不足的三氧化钼和三氧化钨的混合物进行碳热预还原，生成了预还原的残留少量二氧化钨的钨钼复合粉末。此后，将获得的反应产物进行氢还原以除去残留的二氧化钛，并生成粒径为100-200 nm的纯钨-钼复合粉末。制备了两种超细钨钼合金粉末（Mo-30 wt％W，Mo-70 wt％W）。氢还原后，最终获得的产品的残留碳约为0.01-0.02 wt％。研究了超细钨钼粉的烧结行为和样品的性能。在1600°C下烧结极细的Mo-30 wt％W和Mo-70 wt％W粉末后，烧结体的相对密度分别约为99％，97％和显微硬度，分别为287 HV和350 HV。同时，随着烧结温度从1200℃增加到1600℃，压坯的相对密度和显微硬度逐渐增加。